There are applications in industry, government and other organizations where a number of items need to be put together into an ordered set from a number of ordered subsets. Such a problem arises, for example, where magazines, newspapers, or other publications are mailed to readers and, in order to comply with post office regulations, the publications must be ordered according to the postal code of addressees. However, the publications might come from different printing presses or different processing apparatuses and cannot be put together into an ordered set simply by combining the subsets, without some additional processing.
One specific example of the need for such a collation apparatus and mechanism is the magazine publishing industry. Current technology allows magazine publishers to customize magazine editions such that different readers might see different versions of the same magazine. For example, a version mailed to a car enthusiast might contain advertisements for cars, while a version of the same magazine mailed to a golf enthusiast might contain advertisements for golfing equipment. While these different versions of the same magazine might be printed on the same press in order of mailing addresses, they frequently have envelopes attached to them that will bear reader-specific information, such as subscription or advertising information. Thus, it is necessary to keep the envelopes ordered in correspondence with the order of the magazines, so that magazines containing reader-specific information may be efficiently attached to envelopes containing corresponding reader-specific information. Although “intelligent inserting machines” exist which allow envelopes to be stuffed in original list order with reader-specific content, these machines are typically much larger, much more expensive, and far less efficient than “non-intelligent” inserting machines. Therefore, for greater efficiency, the envelopes are often separated into subsets, based on the material that will be stuffed into the envelopes, and are stuffed separately in “non-intelligent” inserting machines. After all the envelopes in each subset are stuffed, the subsets must be collated into a single set, with the order of this set matching that of the order of the magazines, so that the envelopes can then be attached to the magazines. Each subset will be sorted internally, but in order to put them together, they must be additionally collated, so that the whole set is ordered. Therefore, collation is an important production process.
For the above magazine publishing industry example, it is important that the collation be done efficiently and with minimal errors. The reason for this is that even a single error might result in an offset in the collated set, which could result in subsequent addressees not receiving magazines targeted for them. Such efficiency and error-free operation are also important in applications other than magazine publishing. Current methodologies for collating articles from subsets into an ordered set are often inefficient, sometimes even being done by hand. Therefore, a need exists for a system and method for collating articles in an efficient, one-pass manner, that also minimizes errors and the consequences thereof.